CN217788226U

CN217788226U - On-off device

Info

Publication number: CN217788226U
Application number: CN202221139357.4U
Authority: CN
Inventors: 不公告发明人
Original assignee: Shenzhen Nanyun Microelectronics Co ltd
Current assignee: Shenzhen Nanyun Microelectronics Co ltd
Priority date: 2022-05-12
Filing date: 2022-05-12
Publication date: 2022-11-11
Anticipated expiration: 2032-05-12

Abstract

The utility model discloses an on-off device for four end structures, include: the first breakpoint and the second breakpoint are in linkage work, namely, the first breakpoint and the second breakpoint are closed and opened simultaneously during work; one end of a first breakpoint is connected with one end of a first arc extinguishing circuit and then connected with a first end of the on-off device, the other end of the first breakpoint is connected with one end of a second arc extinguishing circuit and then connected with a second end of the on-off device, one end of a second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a third end of the on-off device, and the other end of the second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a fourth end of the on-off device; the first arc extinguishing circuit and the second arc extinguishing circuit are used for extinguishing electric arcs generated when the first breaking point and the second breaking point are broken. The utility model discloses an on-off device is applicable to the one-way power supply system of direct current and the two-way power supply system of direct current simultaneously.

Description

On-off device

Technical Field

The patent of the utility model relates to an extinguish the electric arc of breakpoint when the disconnection, in particular to on-off device.

Background

The arc is a physical phenomenon which is often encountered when a break point formed by a mechanical switch such as a contactor, a circuit breaker, a relay, a connector, a plug, a fuse link and the like is broken, because when the break point breaks current, the break point and a medium around the break point contain a large amount of electrons which can be dissociated, and when an external voltage and a break point contact point are heated sufficiently, strong electric dissociation and thermal dissociation are generated to cause the medium to be punctured, so that the arc is generated. Electric arc harm is very big, can influence power supply system's reliability on the one hand, and on the other hand probably causes incident such as conflagration, consequently need take necessary arc extinguishing measure reliably to extinguish electric arc, the utility model discloses the breakpoint that will contain the arc extinguishing measure is called the on-off unit.

For a direct current power supply system, the current cannot naturally zero, and arc extinguishing measures are generally required; for ac power supply systems, arc extinguishing measures are generally required even when the capacity is 10A or more. General arc extinguishing measure is, installs the explosion chamber that contains structures such as arc extinguishing bars piece or baffle additional, and this can make on-off device's structure comparatively complicated, arouses the increase of volume to a certain extent to and the rising of cost.

However, for the on-off device including two breakpoints in the power supply system, when the two breakpoints are arranged in different lines of the power supply device, an arc extinguishing circuit is generally arranged, and the arc extinguishing circuit is connected in parallel with one of the breakpoints or located on one side of the two breakpoints. Fig. 1 is a circuit diagram of an embodiment of the switching device in the patent document with publication number CN215580357U, wherein an arc extinguishing circuit is connected in parallel with a first break point K1, and a second break point K2 is controlled to be disconnected by a control module after the first break point K1 is disconnected. Fig. 2 is a circuit diagram of an embodiment of the switching device in the patent document with publication number CN1082247A, in which the arc extinguishing circuit is located at one side of two breaking points.

It is noted that the above information disclosed in this background section is only for enhancement of understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information constitutes prior art already known to a person skilled in the art.

SUMMERY OF THE UTILITY MODEL

With this in mind, the present invention provides an on/off device to solve at least one of the technical problems of the prior art to a certain extent.

Therefore, the utility model provides an on-off device's embodiment as follows:

an on-off device having a four-terminal configuration, comprising: the first breakpoint and the second breakpoint are in linkage work, namely, the first breakpoint and the second breakpoint are closed and opened simultaneously during work; one end of the first breakpoint is connected with one end of the first arc extinguishing circuit and then connected with a first end of the on-off device, the other end of the first breakpoint is connected with one end of the second arc extinguishing circuit and then connected with a second end of the on-off device, one end of the second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a third end of the on-off device, and the other end of the second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a fourth end of the on-off device; the first arc extinguishing circuit and the second arc extinguishing circuit are used for extinguishing electric arcs generated by the first breakpoint and the second breakpoint when the first breakpoint and the second breakpoint are disconnected, and only one arc extinguishing circuit works when the electric arcs generated by the first breakpoint and the second breakpoint when the first breakpoint and the second breakpoint are extinguished are different according to the direction of the current flowing in the first breakpoint.

Further, the first breakpoint and/or the second breakpoint is a breakpoint formed by a moving contact and a fixed contact of the contactor, a breakpoint formed by a moving contact and a fixed contact of the relay, a breakpoint formed by a moving contact and a fixed contact of the circuit breaker, or a breakpoint formed by an insert of the plug and a slot corresponding to the socket.

Further, the first arc extinguishing circuit and/or the second arc extinguishing circuit is a non-control type arc extinguishing circuit.

As a specific embodiment of the first and second arc extinguishing circuits, wherein:

the first arc extinguishing circuit comprises a diode D1a, a diode D2a, a capacitor C1a and a first one-way clamping device, wherein the cathode of the diode D1a is connected with the anode of the diode D2a and then serves as one end of the first arc extinguishing circuit, the anode of the diode D1a and the cathode of the diode D2a are simultaneously connected with one end of the capacitor C1a, the other end of the capacitor C1a serves as the other end of the first arc extinguishing circuit, and the first one-way clamping device is connected with the capacitor C1a in parallel;

the second arc extinguishing circuit comprises a diode D1b, a diode D2b, a capacitor C1b and a second one-way clamping device, the cathode of the diode D1b is connected with the anode of the diode D2b and then serves as one end of the second arc extinguishing circuit, the anode of the diode D1b and the cathode of the diode D2b are simultaneously connected with one end of the capacitor C1b, the other end of the capacitor C1b serves as the other end of the second arc extinguishing circuit, and the second one-way clamping device is connected with the capacitor C1b in parallel.

As a specific embodiment of said first unidirectional clamp device and said second unidirectional clamp device, wherein:

the first one-way clamping device is a diode D3a, the cathode of the diode D3a is connected with one end of the capacitor C1a, and the anode of the diode D3a is connected with the other end of the capacitor C1 a;

the second one-way clamping device is a diode D3b, the cathode of the diode D3b is connected with one end of the capacitor C1b, and the anode of the diode D3b is connected with the other end of the capacitor C1 b.

As another specific embodiment of the first unidirectional clamp device and the second unidirectional clamp device, wherein:

the first one-way clamping device is a diode D3a, the anode of the diode D3a is connected with one end of the capacitor C1a, and the cathode of the diode D3a is connected with the other end of the capacitor C1 a;

the second one-way clamping device is a diode D3b, the anode of the diode D3b is connected with one end of the capacitor C1b, and the cathode of the diode D3b is connected with the other end of the capacitor C1 b.

As an equivalent alternative to the above embodiment, the diode D3a therein and/or the diode D3b therein is replaced by: a plurality of diodes are connected in series in the same direction, a unidirectional TVS tube or a plurality of unidirectional TVS tubes are connected in series in the same direction, or the diodes and the unidirectional TVS tubes are combined in any number and then connected in series in the same direction.

the first arc extinguishing circuit comprises a diode D1a, a diode D2a, a capacitor C1a and a first bidirectional clamping device, wherein the cathode of the diode D1a is connected with the anode of the diode D2a and then serves as one end of the first arc extinguishing circuit, the anode of the diode D1a and the cathode of the diode D2a are simultaneously connected with one end of the capacitor C1a, the other end of the capacitor C1a serves as the other end of the first arc extinguishing circuit, and the first bidirectional clamping device is connected with the capacitor C1a in parallel;

the second arc extinguishing circuit comprises a diode D1b, a diode D2b, a capacitor C1b and a second bidirectional clamping device, the cathode of the diode D1b is connected with the anode of the diode D2b and then serves as one end of the second arc extinguishing circuit, the anode of the diode D1b and the cathode of the diode D2b are simultaneously connected with one end of the capacitor C1b, the other end of the capacitor C1b serves as the other end of the second arc extinguishing circuit, and the second bidirectional clamping device is connected with the capacitor C1b in parallel.

As a specific embodiment of said first and second clamp devices, wherein:

the first bidirectional clamping device and/or the second bidirectional clamping device is a bidirectional TVS tube or a plurality of bidirectional TVS tubes connected in series, a piezoresistor or a plurality of piezoresistors connected in series, a gas discharge tube or a plurality of gas discharge tubes connected in series, or a bidirectional TVS tube, a piezoresistor and a gas discharge tube connected in series after being combined in any type and any number.

Furthermore, the on-off device is suitable for a two-wire power supply system, a first end and a second end of the on-off device are used for being connected to one line of the two-wire power supply system, and a third end and a fourth end of the on-off device are used for being connected to the other line of the two-wire power supply system.

As an equivalent alternative to all the above embodiments, any one, any two, any three or four of the diode D1a, the diode D2a, the diode D1b and the diode D2b may be replaced by: a plurality of diodes are connected in series in the same direction, a unidirectional TVS tube or a plurality of unidirectional TVS tubes are connected in series in the same direction, or the diodes and the unidirectional TVS tubes are combined in any number and then connected in series in the same direction.

Compared with the prior art, the embodiment of the utility model provides a following beneficial effect has at least:

1. the embodiment of the utility model provides an in the on-off device include two arc extinguishing circuit to when the electric current flows to the other end from the one end of first breakpoint, or when flowing to one end from the other end of first breakpoint, one of them arc extinguishing circuit work, extinguish the electric arc of corresponding breakpoint, after this breakpoint electric arc extinguishes and breaks off, the electric current that wherein flows through can become zero at once, the electric arc of another breakpoint can extinguish immediately and realize breaking along with it and divide absolutely, thereby make the on-off device not only be applicable to the one-way power supply system of direct current, still be applicable to the two-way power supply system of direct current.

2. The utility model discloses the on-off device can not make great change to the outward appearance of device to still be four terminal structure, can be compatible with the on-off device that adopts prior art, thereby can not change the user custom.

3. The embodiment of the utility model provides an arc extinguishing circuit constitutes for electronic components, adopts the scheme that the explosion chamber carries out the arc extinguishing in prior art relatively, can simplify the structure of on-off device to reduce volume, reduce cost.

4. The first arc extinguishing circuit in this embodiment is connected between first breakpoint one end and second breakpoint one end, and second arc extinguishing circuit is connected between the first breakpoint other end and the second breakpoint other end to guaranteed that whole on-off device satisfies the physical isolation requirement.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

FIG. 1 is a circuit diagram of an embodiment of a switching device disclosed in the patent document with publication number CN 215580357U;

FIG. 2 is a circuit diagram of an embodiment of the on-off device disclosed in the patent publication No. CN 1082247A;

fig. 3 is a schematic block diagram of an embodiment of the on-off device of the present invention;

fig. 4 is a specific circuit diagram of an embodiment of the on-off device of the present invention and its application;

fig. 5 is a specific circuit diagram of an embodiment of the on-off device of the present invention and an application thereof;

fig. 6 is another specific circuit diagram of the embodiment of the on-off device of the present invention and its application.

Detailed Description

Based on the inventive concept of the present application, it can be understood that the present invention is inventive in that two arc extinguishing circuits are provided in the on-off device, so that when the current flows from one end of the first breakpoint to the other end, or from the other end of the first breakpoint to one end, arc extinguishing can be realized, and no arc extinguishing circuit is specifically adopted, the first arc extinguishing circuit and the second arc extinguishing circuit given in fig. 4 to 6 are only a preferred example, when facing different application scenarios, a person skilled in the art can select or design separately according to the actual situation, and the present invention is not limited thereto.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with other figures are described in detail below, and it is apparent that the described embodiments are some, not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It is to be noted that the terms "comprises" and "comprising," and any variations thereof, as used in the specification and claims of this application, are intended to cover non-exclusive inclusions, such as, for example, the inclusion of a list of elements or unit circuits is not necessarily limited to those elements or unit circuits expressly listed, but may include elements or unit circuits not expressly listed or inherent to such circuits.

In addition, the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It will be understood that when an element is referred to in the specification and claims as being "connected" to another element, it can be "directly connected" to the other element or "connected" to the other element through a third element.

Fig. 3 is a schematic block diagram of an embodiment of the on-off device of the present invention, please refer to fig. 3, the on-off device of this embodiment is a four-end structure, including: the first breakpoint K1, the second breakpoint K2, the first arc extinguishing circuit and the second arc extinguishing circuit; one end of a first breakpoint K1 is connected with one end of a first arc extinguishing circuit and then connected with a first end of the on-off device, the other end of the first breakpoint K1 is connected with one end of a second arc extinguishing circuit and then connected with a second end of the on-off device, one end of a second breakpoint K2 is connected with the other end of the second arc extinguishing circuit and then connected with a third end of the on-off device, and the other end of the second breakpoint K2 is connected with the other end of the second arc extinguishing circuit and then connected with a fourth end of the on-off device; the first arc extinguishing circuit and the second arc extinguishing circuit are used for extinguishing electric arcs generated by the first breakpoint K1 and the second breakpoint K2 when the first breakpoint K1 and the second breakpoint K2 are disconnected, the first arc extinguishing circuit and the second arc extinguishing circuit are different in the flowing direction of current in the first breakpoint K1, and only one arc extinguishing circuit works when the electric arcs generated by the first breakpoint K1 and the second breakpoint K2 when the first breakpoint K1 and the second breakpoint K2 are extinguished are disconnected.

The on-off device in this embodiment includes two arc extinguishing circuits, so that when a current flows from one end of the first breakpoint K1 to the other end, or from the other end of the first breakpoint K1 to one end, one of the arc extinguishing circuits operates to extinguish an arc at a breakpoint connected to a positive terminal of a power supply at the present time, and when the arc at the breakpoint is extinguished and disconnected, the current flowing therethrough will become zero at once, and an arc at the other breakpoint will be extinguished immediately and then disconnected, so that the on-off device is not only suitable for a dc unidirectional power supply system, but also suitable for a dc bidirectional power supply system.

The on-off device of this embodiment does not significantly change the appearance of the device and is still of a four terminal construction, compatible with on-off devices employing prior art, and thus does not change user habits.

Compared with the scheme that an arc extinguishing chamber is adopted for arc extinguishing in the prior art, the structure of the on-off device can be simplified, so that the size is reduced, and the cost is reduced.

First arc extinguishing circuit in this embodiment is connected between first breakpoint K1 one end and second breakpoint K2 one end, and second arc extinguishing circuit is connected between the first breakpoint K1 other end and the second breakpoint K2 other end to it satisfies the physical isolation requirement to have ensured whole on-off device.

Further, the first breakpoint K1 and/or the second breakpoint K2 are breakpoints formed by a moving contact and a fixed contact of the contactor, a moving contact and a fixed contact of the relay, a moving contact and a fixed contact of the circuit breaker, or a plug blade of the plug and a slot corresponding to the socket.

Furthermore, the first arc extinguishing circuit and/or the second arc extinguishing circuit are/is a non-controlled arc extinguishing circuit, namely, no element which can work only by detection and triggering is arranged in the arc extinguishing circuit, such as a controlled silicon, a thyristor and the like, so that the complexity of the device is avoided being increased.

Fig. 4 is a specific circuit diagram of an embodiment of the on-off device of the present invention and its application, please refer to fig. 4:

the first arc extinguishing circuit comprises a diode D1a, a diode D2a, a capacitor C1a and a first one-way clamping device, the cathode of the diode D1a is connected with the anode of the diode D2a to form one end of the first arc extinguishing circuit, the anode of the diode D1a and the cathode of the diode D2a are simultaneously connected with one end of the capacitor C1a, the other end of the capacitor C1a is the other end of the first arc extinguishing circuit, and the first one-way clamping device is connected with the capacitor C1a in parallel;

the second arc extinguishing circuit comprises a diode D1b, a diode D2b, a capacitor C1b and a second one-way clamping device, one end of the second arc extinguishing circuit is formed after the cathode of the diode D1b is connected with the anode of the diode D2b, one end of the capacitor C1b is connected with the anode of the diode D1b and the cathode of the diode D2b at the same time, the other end of the capacitor C1b is the other end of the second arc extinguishing circuit, and the second one-way clamping device is connected with the capacitor C1b in parallel.

The first one-way clamping device is a diode D3a, the cathode of the diode D3a is connected with one end of a capacitor C1a, and the anode of the diode D3a is connected with the other end of the capacitor C1 a; the second one-way clamping device is a diode D3b, the cathode of the diode D3b is connected with one end of the capacitor C1b, and the anode of the diode D3b is connected with the other end of the capacitor C1 b.

The working process of the first breaking point K1 and the second breaking point K2 for the arc extinguishing circuit to extinguish the arc during the breaking process is described below with reference to fig. 4. In the circuit in fig. 4, when a current flows from one end of the first breakpoint K1 to the other end, wherein the power supply U1 supplies power to the load RL1, the positive end of the power supply U1 is connected to one end of the first breakpoint K1, and the on-off device is connected to the power supply system, the diode D2a is turned on, the capacitor C1a is charged, and the first arc extinguishing circuit does not work any more after the capacitor C1a is fully charged; first breakpoint K1 and second breakpoint K2 are after first closure, and diode D2b switches on, and electric capacity C1b charges, and first breakpoint K1 and second breakpoint K2 are in follow-up breaking process, realize earlier the arc extinguishing to first breakpoint K1 by second arc extinguishing circuit, after first breakpoint K1 electric arc extinguishes and breaks off, and wherein the electric current that flows through can become zero at once, and the electric arc of second breakpoint K2 can extinguish immediately and realize breaking thereupon, and the concrete process that second arc extinguishing circuit realized the arc extinguishing to first breakpoint K1 is as follows:

(1) Ignition arc stage

When the first breaking point K1 starts to open, strong electric dissociation and thermal dissociation can be generated between the contacts, so that the air medium around the contacts is broken down, and an electric arc is ignited.

(2) Arc sustained combustion phase

After the arc is ignited, along with the gradual increase of the contact gap of the first breakpoint K1, the rate of the decrease of the arc resistance caused by the temperature increase is smaller than the rate of the increase of the arc resistance caused by the increase of the gap, the arc resistance starts to increase, the voltage generated at the two ends of the load RL1 is reduced, the increasing trend of the voltage UK1 at the two ends of the first breakpoint K1 is ensured, and the arc combustion process enters a dynamic stable state. The rising rate of the voltage UK1 at the two ends of the first breakpoint K1 and the reduction rate of the current I1 flowing through the first breakpoint K1 can achieve the condition of stable combustion of the arc, namely, the relation between the voltage value UK1 and the current value I1 can move along the negative resistance characteristic curve graph of the arc and be automatically adjusted.

(3) At the moment of current injection, the conditions for stable combustion of the arc are destroyed

When the voltage across the load RL1 is reduced to a value that the voltage across the load RL1 is smaller than the voltage U1 of the power supply minus the forward conduction voltage drop of the diode D1b, the diode D1b is turned on, the capacitor C1b discharges to inject the current I2 into the load RL1, so that the current I3 flowing through the load RL1 and the second breakpoint K2 is changed from I1 to (I1 + I2), the voltages across the load RL1 and the second breakpoint K2 increase, the voltage across the other end of the first breakpoint K1 is raised, the rate of the natural rise of the voltage UK1 across the first breakpoint K1 is reduced, and the stable negative resistance characteristic relationship between the rate of the rise of the voltage UK1 across the first breakpoint K1 and the rate of the reduction of the current I1 flowing through the first breakpoint K1, that is the condition of dynamically stable combustion of the arc is destroyed.

(4) The current is injected continuously, the electric arc burns and enters negative feedback, and the electric arc tends to be extinguished

In the disconnection process of the first breakpoint K1, the gap for separating the contacts is larger and larger, so that the electric arc is stably burnt, the voltage required for puncturing the medium around the contacts is also larger and larger, namely the voltage UK1 at the two ends of the first breakpoint K1 is required to be larger and larger, but along with the injection of the discharge current I2 into the load RL1, the voltage at the other end of the first breakpoint K1 is raised, the rising rate of the voltage UK1 at the two ends of the first breakpoint K1 is smaller than the rate of maintaining the dynamic stable burning of the electric arc, and the electric arc burning enters negative feedback circulation, namely, the electric arc is smaller and tends to be extinguished.

(5) Parasitic inductance back electromotive force follow current stage

When the load RL1 includes an inductive load such as a motor, parasitic inductance is generated. After the arc burning enters a negative feedback state, the reduction rate of the current I1 is very high, the current in the parasitic inductance is not allowed to change suddenly (the parasitic inductance is more obvious when the parasitic inductance is larger), and the parasitic inductance can generate a reverse electromotive force, a circuit loop is formed by the power supply U1, the first breakpoint K1, the load RL1 and the second breakpoint K2, namely, an additional power supply is connected in series between the first breakpoint K1 and the power supply U1, and the power supply is connected in series with the power supply U1 in the same direction, so that the voltage at two ends of the first breakpoint K1 is increased.

The energy in the capacitor C1b is firstly drawn away by the back electromotive force generated by the parasitic inductance, then the capacitor C1b is charged, when the capacitor C1b is fully charged (the capacitor C1b is restored to the state capable of extinguishing the arc again, and energy injection is provided when the first breakpoint K1 is disconnected again), the excess energy in the parasitic inductance will follow current through a loop formed by the load RL1, the diode D3b and the diode D1b, and the diode D3b and the diode D1b will change the back electromotive force (back voltage, that is, the voltage at the other end of the first breakpoint K1) of the load RL1 into the sum of the forward conduction voltage drop of the clamping diode D3b and the forward conduction voltage drop of the diode D1b, so that the voltage at the two ends of the first breakpoint K1 is prevented from being continuously increased, and thus the tendency of arc extinguishing is not changed, and the arc is ensured. Meanwhile, the capacitance value required by effective arc extinction of the capacitor C1b alone is greatly reduced, the cost is reduced, and the capacitor C1b can be prevented from being broken down and damaged due to the fact that the capacitor C1b bears overhigh voltage.

In the circuit of fig. 4, since the voltage at the other end of the first breakpoint K1 is clamped to the sum of the forward conduction voltage drop of the diode D3b and the forward conduction voltage drop of the diode D1b, the voltage is about 2V, the arc at the first breakpoint K1 is rapidly extinguished, and the arc at the second breakpoint K2 is also extinguished accordingly.

In the embodiment, the diode D3b and the diode D1b are connected in series in the same direction, the total clamping voltage is the sum of the clamping voltages of the two components, the voltage stress required to be borne by the clamping device is dispersed, and the risk of failure of the clamping device is reduced.

(6) Moment of arc extinction

When the gap between the contacts of the first breaking point K1 is continuously increased, the arc resistance is further increased, so that the arc current (i.e., the current I1) is further decreased, and when the arc current is decreased to such a level that the arc cannot be maintained, the discharge disappears, and at this time, the arc is extinguished.

When the current flows to one end from the other end of the first breakpoint K1, the power supply U2 supplies power to the load RL2, the positive end of the power supply U2 is connected with the other end of the first breakpoint, and after the on-off device is connected to the power supply system, the capacitor C1b is fully charged, so that the second arc extinguishing circuit does not work any more, the diode D2a is turned on after the first breakpoint K1 and the second breakpoint K2 are closed for the first time, the capacitor C1a is charged, the first breakpoint K1 and the second breakpoint K2 realize arc extinguishing by the first arc extinguishing circuit in the subsequent breaking process, the arc extinguishing process is consistent with the above process, and details are omitted.

Fig. 5 is another specific circuit diagram of an embodiment of the on-off device of the present invention and an application thereof, please refer to fig. 5, which is different from fig. 4 in that: the anode of the diode D3a is connected with one end of the capacitor C1a, and the cathode of the diode D3a is connected with the other end of the capacitor C1 a; the anode of the diode D3b is connected with one end of the capacitor C1b, and the cathode of the diode D3b is connected with the other end of the capacitor C1 b.

At this time, when the current in the circuit in fig. 5 flows from the other end of the first breakpoint K1 to one end, the power supply U1 supplies power to the load RL1, the negative end of the power supply U1 is connected with one end of the first breakpoint, the on-off device is connected to the power supply system, the diode D1a is turned on, the capacitor C1a is charged, the first arc extinguishing circuit does not work any more after the capacitor C1a is fully charged, and the capacitor C1b is fully charged after the first breakpoint K1 and the second breakpoint K2 are closed. In the process of disconnecting the first breakpoint K1 and the second breakpoint K2, the second arc extinguishing circuit firstly extinguishes the second breakpoint K2, after the arc at the second breakpoint K2 is extinguished and disconnected, the current flowing through the second breakpoint K2 is immediately zero, and the arc at the first breakpoint K1 is immediately extinguished and then disconnected. Specifically, when the voltage of the load RL1 is reduced to a value that the voltage of the anode of the diode D2b is greater than the voltage of the power supply U1 minus the forward conduction voltage of the diode D2b, at this time, the diode D2b is conducted, energy is injected into the load RL1 through a discharge loop formed by the capacitor C1b, the load RL1 and the diode D2b, the voltage across the load RL1 and the first break point K1 is raised as well, the voltage across the second break point K2 is reduced, and arc extinction can be achieved as well.

When the current flows from one end of the first breakpoint K1 to the other end of the circuit in fig. 5, the power supply U2 supplies power to the load RL2, the negative end of the power supply U2 is connected to the other end of the first breakpoint, the on-off device is connected to the power supply system, the diode D1b is turned on, the capacitor C1b is charged, the second arc extinguishing circuit does not work any more after the capacitor C1b is fully charged, and the capacitor C1a is fully charged after the first breakpoint K1 and the second breakpoint K2 are closed. In the process of disconnecting the first breakpoint K1 and the second breakpoint K2, the first arc extinguishing circuit firstly carries out arc extinguishing on the second breakpoint K2, after the electric arc at the second breakpoint K2 is extinguished and disconnected, the current flowing through the second breakpoint K2 is immediately zero, and the electric arc at the first breakpoint K1 is immediately extinguished and then disconnected. Specifically, when the voltage of the load RL2 is reduced to a value that the voltage of the anode of the diode D2a is greater than the voltage of the power supply U2 minus the forward conduction voltage of the diode D2a, at this time, the diode D2a is conducted, energy is injected into the load RL2 through a discharge loop formed by the capacitor C1a, the load RL2 and the diode D2a, the voltage across the load RL2 and the first break point K1 is raised as well, the voltage across the second break point K2 is reduced, and arc extinction can be achieved as well.

Based on the above description, it is conceivable to optimize fig. 4 and 5 as follows:

replacing the diode D3a therein and/or the diode D3b therein with: a plurality of diodes syntropy are established ties, one unidirectional TVS pipe or a plurality of unidirectional TVS pipe syntropy are established ties, or the diode syntropy is established ties after arbitrary quantity and the arbitrary quantity combination of unidirectional TVS pipe, and the withstand voltage requirement to the device not only can further be reduced to the purpose that adopts a plurality of devices to establish ties, the magnitude of the voltage value that restricts when can also adjusting reverse electromotive force voltage and restrict.

Fig. 6 is another specific circuit diagram of an embodiment of the on-off device of the present invention and its application, please refer to fig. 6:

the first arc extinguishing circuit comprises a diode D1a, a diode D2a, a capacitor C1a and a first bidirectional clamping device, the cathode of the diode D1a is connected with the anode of the diode D2a to form one end of the first arc extinguishing circuit, the anode of the diode D1a and the cathode of the diode D2a are simultaneously connected with one end of the capacitor C1a, the other end of the capacitor C1a is the other end of the first arc extinguishing circuit, and the first bidirectional clamping device is connected with the capacitor C1a in parallel;

the second arc extinguishing circuit comprises a diode D1b, a diode D2b, a capacitor C1b and a second bidirectional clamping device, the cathode of the diode D1b is connected with the anode of the diode D2b to form one end of the second arc extinguishing circuit, the anode of the diode D1b and the cathode of the diode D2b are simultaneously connected with one end of the capacitor C1b, the other end of the capacitor C1b is the other end of the second arc extinguishing circuit, and the second bidirectional clamping device is connected with the capacitor C1b in parallel.

The first bidirectional clamping device is a bidirectional TVS tube T1a, and the second bidirectional clamping device is a bidirectional TVS tube T1b.

The operating principle of the circuit shown in fig. 6 is different from that of the circuit shown in fig. 4 in that the on-off device can be applied not only to a direct-current unidirectional power supply system and a direct-current bidirectional power supply system, but also to an alternating-current power supply system. When applied to a direct current unidirectional power supply system and a direct current bidirectional power supply system, the arc extinguishing process is the same as that of the on-off device in the circuit shown in fig. 4. When the arc extinguishing device is applied to an alternating current power supply system, taking the power supply U1 as an alternating current power supply to supply power to the load RL1, and taking the case that the on-off device needs to be disconnected when the current flows from the other end of the first breakpoint K1 to one end as an example, the difference of the arc extinguishing process is described as follows:

after the on-off device is connected into a power supply system, the diode D1a is conducted, the capacitor C1a is charged, the first arc extinguishing circuit does not work any more after the capacitor C1a is fully charged, and the capacitor C1b is fully charged after the first breakpoint K1 and the second breakpoint K2 are closed. In the process of disconnecting the first breakpoint K1 and the second breakpoint K2, the second arc extinguishing circuit firstly carries out arc extinguishing on the second breakpoint K2, after the electric arc at the second breakpoint K2 is extinguished and disconnected, the current flowing through the second breakpoint K2 is immediately zero, and the electric arc at the first breakpoint K1 is immediately extinguished and then disconnected. Specifically, when the voltage of the load RL1 is reduced to a value that the voltage of the anode of the diode D2b is greater than the voltage of the power supply U1 minus the forward conduction voltage of the diode D2b, at this time, the diode D2b is conducted, energy is injected into the load RL1 through a discharge loop formed by the capacitor C1b, the load RL1 and the diode D2b, the voltage across the load RL1 and the first break point K1 is raised as well, the voltage across the second break point K2 is reduced, and arc extinction can be achieved as well.

It should be noted that, in the circuit shown in fig. 6, since the clamped voltage value is the sum of the clamping voltage of the bidirectional TVS and the forward conduction voltage drop of the diode, the general selection principle of the maximum reverse operating voltage of the bidirectional TVS is as follows: the dc voltage is 1.1-1.2 times or 1.4 times of the ac voltage, so the arc extinguishing speed of the circuit shown in fig. 6 is slower than that of the circuit shown in fig. 4, but the application scenarios are wider, and those skilled in the art can select which circuit to use according to the actual situation.

Based on the above description, it is conceivable to optimize fig. 6 as follows:

replacing the bidirectional TVS tube T1a and/or the bidirectional TVS tube T1b with: a plurality of two-way TVS pipes are established ties, a piezo-resistor or a plurality of piezo-resistor establish ties, a gas discharge tube or a plurality of gas discharge tubes establish ties, or establish ties after two-way TVS pipe, piezo-resistor and gas discharge tube arbitrary kind and arbitrary quantity combination. The purpose of using a plurality of devices in series is to not only further reduce the withstand voltage requirement for the devices, but also to adjust the magnitude of the voltage value limited when the back electromotive voltage is limited.

It should be noted that, as can be seen from the application scenarios shown in fig. 4 to fig. 6, the on-off device according to the embodiment of the present invention is suitable for the two-wire power supply system, the first end and the second end of the on-off device are used for being connected to one line of the two-wire power supply system, and the third end and the fourth end of the on-off device are used for being connected to the other line of the two-wire power supply system.

Furthermore, it is conceivable to optimize fig. 4 to 6 as follows:

any one, any two, any three or four of the diode D1a, the diode D2a, the diode D1b and the diode D2b are replaced by: a plurality of diodes syntropy are established ties, one unidirectional TVS pipe or a plurality of unidirectional TVS pipe syntropy are established ties, or the diode syntropy is established ties after arbitrary quantity and the arbitrary quantity combination of unidirectional TVS pipe, not only can reduce the withstand voltage requirement to the device, can also adjust the moment that the electric current pours into.

The above are only embodiments of the present invention, and it should be especially noted that the above embodiments should not be considered as limitations of the present invention, and for those skilled in the art, a plurality of modifications and decorations can be made without departing from the spirit and scope of the present invention, and these modifications and decorations should also be considered as protection scope of the present invention.

Claims

1. An on-off device of four-terminal configuration, comprising: the first breakpoint and the second breakpoint are in linkage work, namely, the first breakpoint and the second breakpoint are closed and opened simultaneously during work; one end of the first breakpoint is connected with one end of the first arc extinguishing circuit and then connected with a first end of the on-off device, the other end of the first breakpoint is connected with one end of the second arc extinguishing circuit and then connected with a second end of the on-off device, one end of the second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a third end of the on-off device, and the other end of the second breakpoint is connected with the other end of the second arc extinguishing circuit and then connected with a fourth end of the on-off device; the first arc extinguishing circuit and the second arc extinguishing circuit are used for extinguishing electric arcs generated when the first breakpoint and the second breakpoint are disconnected, and only one arc extinguishing circuit works when the electric arcs generated when the first breakpoint and the second breakpoint are disconnected are extinguished according to different flowing directions of current in the first breakpoint.

2. The on-off device of claim 1, wherein: the first breakpoint and/or the second breakpoint are/is a breakpoint formed by a moving contact and a fixed contact of the contactor, a breakpoint formed by a moving contact and a fixed contact of the relay, a breakpoint formed by a moving contact and a fixed contact of the circuit breaker, or a breakpoint formed by an insertion sheet of the plug and a slot corresponding to the socket.

3. The on-off device according to claim 1, wherein: the first arc extinguishing circuit and/or the second arc extinguishing circuit are/is a non-control arc extinguishing circuit.

4. The on-off device of claim 1, wherein:

5. The on-off device according to claim 4, wherein:

6. The on-off device according to claim 5, wherein: replacing the diode D3a therein and/or the diode D3b therein with: a plurality of diodes are connected in series in the same direction, a unidirectional TVS tube or a plurality of unidirectional TVS tubes are connected in series in the same direction, or the diodes and the unidirectional TVS tubes are combined in any number and then connected in series in the same direction.

7. The on-off device according to claim 4, wherein:

8. The on-off device according to claim 7, wherein: replacing the diode D3a therein and/or the diode D3b therein with: a plurality of diodes are connected in series in the same direction, a unidirectional TVS tube or a plurality of unidirectional TVS tubes are connected in series in the same direction, or the diodes and the unidirectional TVS tubes are combined in any number and then connected in series in the same direction.

9. The on-off device of claim 1, wherein:

10. The on-off device according to claim 9, wherein: the first bidirectional clamping device and/or the second bidirectional clamping device is formed by connecting one bidirectional TVS tube or a plurality of bidirectional TVS tubes in series, connecting one piezoresistor or a plurality of piezoresistors in series, connecting one gas discharge tube or a plurality of gas discharge tubes in series, or connecting the bidirectional TVS tubes, the piezoresistors and the gas discharge tubes in series after any kinds and any number of combinations.

11. The on-off device according to claim 1, wherein: the on-off device is suitable for a two-wire power supply system, a first end and a second end of the on-off device are used for being connected to one line of the two-wire power supply system, and a third end and a fourth end of the on-off device are used for being connected to the other line of the two-wire power supply system.

12. The on-off device according to any of the claims 4 to 11, characterized in that any one, any two, any three or four of the diode D1a, the diode D2a, the diode D1b and the diode D2b is replaced by: a plurality of diodes are connected in series in the same direction, a unidirectional TVS tube or a plurality of unidirectional TVS tubes are connected in series in the same direction, or the diodes and the unidirectional TVS tubes are combined in any number and then connected in series in the same direction.